CREDIT card NIGHTMARES

This is LITERALLY the worst bank in the world, i have had so many issues with them and i've only been with them for two months.... So the latest issue i have is , i app**** for a credit card , received a few emails requesting my documents so i sent them through, i then received an email on the 19th September stating that my credit card application has been accepted and that my credit card will be delivered in 3 - 5 working days, i received my credit card on the 28th September, i tried to activate it but nothing happens so i phoned them ... TWICE the first time a lady said that i have to go into the branch to activate it and get my pin (I already had my pin) so i said no wait this cant be so i phoned again and this lady said that i hadnt given all my documents in , which was also not true so i decided to go into the branch on Saturday sat there for 3 and a half hours, they phoned the credit card division and THEY said that my credit card was DECLINED on the 17th of September , so i asked on what grounds? but nobody seems to know what is going on. How can i have received confirmation of it being approved on the 19th if they declined it on the 17th ??? that makes NO sense , the credit card was meant for emergencies but it has caused so much hassle and worries and its not even in debt or use , i have this card that is of no use to me, The lady from the branch said that she will be in contact with me on Monday the 1st of October..... obviously to no avail .... WHAT IS GOING ON????